Tuning oxygen vacancies in epitaxial LaInO3 films for ultraviolet photodetection

LaInO3 (LIO) represents a new, to the best of knowledge, type of perovskite oxides for deep-ultraviolet (DUV) pho-todetection owing to the wide bandgap nature (similar to 5.0 eV) and the higher tolerance of defect engineering for tunable carrier transport. Here we fabricate fast-response DUV photode-tectors based on epitaxial LIO thin films and demonstrate an effective strategy for balancing the photodetector per-formance using the oxygen growth pressure as a simple control parameter. Increasing the oxygen pressure is effec-tive to suppress the oxygen vacancy formation in LIO, which is beneficial to suppress the dark current and enhance the response speed. The optimized LIO photodetector achieves a fast rise/fall time of 20 ms/73 ms, a low dark current of 2.0 x 10-12 A, a photo-to-dark current ratio of 1.2 x 103, and a detectivity of 6 x 1012 Jones. (c) 2022 Optica Publishing Group